Question

At an early stage of clinical trials of a certain method of gender​ selection, 14 couples using that method gave birth to 13 boys and 1 girl. Complete parts​ (a) through​ (e) below.

a. Assuming that the method has no effect and boys and girls are equally​ likely, use the range rule of thumb to identify the limits separating values that are significantly low and those that are significantly high​ (for the number of boys in 14 ​births). Based on the​ results, is the result of 13 boys significantly high​?

Significantly low values for the number of boys in 14 births are _____ and lower. Significantly high values for the number of boys in 14 births are ____ and higher. The result of 13 boys (is or is not?) significantly high. ​(Type integers or decimals rounded to one decimal place as​ needed.)

b. Find the probability of exactly 13 boys in 14 ​births, assuming that the method has no effect. _______ ​(Type an integer or decimal rounded to six decimal places as​ needed.)

c. Find the probability of 13 or more boys in 14 ​births, assuming that the method has no effect. _____ ​(Type an integer or decimal rounded to six decimal places as​ needed.)

d. Which probability is relevant for determining whether 13 boys is significantly high​: the probability from part​ (b) or part​ (c)? Based on the relevant​ probability, is the result of 13 boys significantly high​?

The probability from (Part C or Part B) is relevant for determining whether 13 boys is significantly high. Based on this​ probability, the result of 13 boys (is or is not) significantly high.

e. What do the results suggest about the effectiveness of this method of gender​ selection?

A. The results do not suggest anything about the effectiveness of this method of gender selection.

B. The results suggest that this method is not effective at transforming the distribution of genders to a binomial distribution.

C. The results suggest that this method is effective at transforming the distribution of genders to a binomial distribution. D. The results suggest that this method is not effective in increasing the likelihood that a baby is a boy.

E. The results suggest that this method is effective in increasing the likelihood that a baby is a boy.

Answer 1

(a) Significantly low values for the number of boys in 14 births are 3.3 and lower. Significantly high values for the number of boys in 14 births are 10.7 and higher. The result of 13 boys is significantly high.

(b) 0.000854

(c) 0.000916

(d) The probability from Part C is relevant for determining whether 13 boys is significantly high. Based on this​ probability, the result of 13 boys is significantly high.

(e) E. The results suggest that this method is effective in increasing the likelihood that a baby is a boy.